WATER SOILS. • 229 



and Milan, 1764-1900. There is shown to be a 35-j^ear periodicity as regards dry 

 and wet years, corresponding with the 85-year climatic period of Bruckner, as follows: 



Periodicity of icet and dry years. 



Wet 1738 1773 1808 1843 1878 (1913) 



Dry 1753 1788 1823 1859 1898 (1928) 



Black rain in Nortli Carolina, C. Baskerville and H. R. Weller {Scioicc, n. 

 .sec, J6 {1902), No. .197, ])j>. 215, 216). — An abstract of a paper read before the North 

 Carolina section of the American Chemical Society at Raleigh May 17, 1902, which 

 refers briefly to a chemical eyamination of a sample of black rain from Lonis- 

 burg, N. C. * 



Cyclones and agriculture, L. Dumas [Tj^ Tug. Ayr. Gemblou.r, 12 (1902), No. 11, 

 pp. 523-531, Jiyii. 2). — A general dis-cussion of the movement and course of cyclones 

 and of the damage which thev do to agriculture. 



WATER SOILS. 



Waters ( California. Sia. Rpt. 1899-1901, pt. 1, pp. 49, 50). — The results of examina- 

 tions of 310 samples of water from different parts of the State, with reference to their 

 adaptabilitj' for domestic or irrigation purposes, are briefly summarized. It was 

 found that 70 per cent of the lake and stream waters, 56 per cent of the spring 

 waters, 56.7 per cent of the common well waters, 47.8 per cent of the reservoir and 

 ditch waters, and 31.6 per cent of the artesian well waters were unsuitable for 

 domestic and irrigation purposes. 



The purification and sterilization of water, S. Rideal {.four. tSoc. ^l/'/.s, 50 

 (1902), Noii. 2591, pp. 717-725; 2592, pp. 729-737; 2593, pp. 741-750; 2594, pp. 

 755-767). — A series of lectures giving a very complete discussion of the snl)ject. 



Studies of the subterranean hydrology of the region of Cadereyta Mendez, 

 State of dueretaro, 1901, J. DeD. Villarello {Bol. Sec. Fomento [^fexi<■<l'\, 1 

 {1901), No. 5, IY,pp. 75-91; 1 {1902), No. 6, IV, pp. 135-152). 



Soil analyses, C. L. Penny {Delaware Sta. Rpt. 1901, pp. 77-S2, fly. 1). — "As a 

 preliminary step to a general study of the soil, analyses were made for potash, phos- 

 jilioric acid, and lime in 7 soils selected from various places in Kent County, all in 

 the vicinity of Dover." The results of these analyses, as well as of mechanical 

 analyses of the soils, are reported with a description of the methods used in sampling 

 the soils and in determining potash. In each case the surface soil was sampled to 

 the line of demarcation between surface and subsoil, the depth varying from 6 to 10 

 in. in different cases. The subsoil was sampled to a total depth from the surface of 

 36 in., or 25 to 30 in. below the bottom of the surface soil. The samples were taken 

 either with a brass tube sampler or by means of a spade. The method of determining 

 potash was substantially that described in previous publications (K. S. R., 10, pp. 

 K!4, 514), except that the rotary device used in the acid digestion of the soils was 

 modified so that the steam chest containing the flasks is inclined toward the 

 horizon at an angle of 22°, the flasks being placed in the chest with their necks 

 parallel to the axis of rotation. In this way the necessity for tightly closing the 

 flasks, with the consequent danger of collapse, is avoided, and it is claimed that v.hile 

 the agitation is not so violent as in the original device, the conditions are quite as 

 favorable for the solvent action of the acid. The soil solutions were made with 

 hydrochloric acid of 20.26 percent strength (1 liter of acid to 500 gm. of soil), the 

 digestion being maintained at steam heat for 12 hours. Parallel determinations were 



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